The present invention relates to a method and device for additional pressing during a page nipping event in the adhesive binding of books.
The structure currently in common use for page nipping is described in more detail in the following with reference to the accompanying drawings, and in particular to FIGS. 1a, 1b and 1c, which portray the normal course of events as is commonly in use.
The cover 1 may be of any material whatsoever suited for its purpose as the cover material of a soft-covered book. Typically the cover is either paper, board, plastic or a combination of these materials.
The block 2 consists of the book's pages. The pages can typically be of paper, board, plastic or corresponding material. The purpose is for the cover material to be wrapped tightly around the block formed by the pages of the book and then to be attached, for example, by adhesive to the spine of block 2.
Any agent whatsoever, suitable for fastening cover 1 to block 2, may be used as the adhesive material 3. Typically, hot-setting adhesive or cold-dispersion adhesive is used.
Base 4 supports the spine of the book. Built into the base, or attached to it, is a stationary jaw 4′, against which the book, which here refers to the combination of block and cover and the edge of the cover on the compression plate side, are pressed as the movable jaw of the base closes.
Pressing shaft 5 is used to press block 2 and cover 1 tightly against the compression plate 6. Pressing shaft 5 can be anchored for example to compression plate 6, so that it is fastened to the compression plate outside of the book and on both sides of it.
Compression plate 6 is a swivel plate that can be turned around axis A. In FIG. 1a, the swivel plate is in its lower position. The plate can be turned anti clockwise, causing the cover and the block to be released from the base. If it is assumed that no adhesive has yet been applied between the cover and the block, cover 1 will be separated from block 2 during the aforementioned turning movement. The cover being thus removed from the block, adhesive 3 can be applied to the spine of the block. Once the adhesive is applied, the swivel plate is turned back to the position shown in FIG. 1a. 
Flexible guard 7 is fastened to pressing shaft 5 or its connection by taping, gluing, screwing, soldering, welding, riveting, pinching or by other commonly known method. The purpose of flexible guard 7 is to support the book during the application of adhesive.
Flexible guard 7 is typically spring steel band or a corresponding material that may be bent and will return after bending to its original or almost original position A flexible guard is also attached to the compression plate, as a result of which the bending of the book in the area between the pressing shaft and the cover is possible. The bending of the book is also known as fanning and is used to enhance the spreading of adhesive onto the sides of the pages to be bound.
The movable jaw 8 is located between cover 1 and base 4. It opens for at least the width of the book. The movable jaw is used to fold the cover and press it against the block. Movable jaw 8 is kept closed until a sufficiently strong adhesive joint has been established.
At the present time, page nipping is typically executed in the manner presented in FIGS. 1a, 1b and 1c. Initially, as shown in FIG. 1a, cover 1 and block 2 are pressed between pressing shaft 5 and compression plate 6. Between the cover and the paper block is some agglutination agent in a “free” state, meaning that adhesive 3 has not yet solidified. The compression plate is supported in such a way that the cover is in contact with base 4 at the point where it is attached to the paper block.
When movable jaw 8 has closed sufficiently, as shown in FIG. 1b, cover 1 exerts an upward force on the book. When the force is sufficient, some or all of the pages in the block buckle and the cover lifts off from the base where it is attached to the book. When movable jaw 8 has closed, as in FIG. 1c, the spine of the book is pressed between it and the stationary jaw of the base. When the adhesive joint has become sufficiently solid, movable jaw 8 is moved back to the open position.
The disadvantage is that the spine of the book is easily left crooked after the adhesive joint has solidified. This is especially true of some relatively thick board materials that are used for book covers. As a result of this, the appearance of the book is impaired. Crookedness in this context means deviations from a 90 degree angle in the spine of a book and/or the curvature of the spine.